An ooze is a mobile, carnivorous mold that develops in dark, dank places that experience little to no regular traffic. Oozes feed off of ambient bacteria, fungi, and small insects as they grow. They begin to seek larger prey, including humans, once they reach the size of a dog.

Like all living creatures, they have a measure of soul essence, but their lack of intelligence and a true nervous system makes them mindlessly aggressive and difficult to deter. Their viscosity and mobility enable them to perform surprisingly nimble attacks, and they are capable of "spitting" corrosive enzymes to break down flesh and armor. Some of the more dangerous variants of the species are disease vectors, making any confrontation with them especially perilous.